Constants Defining Special Destructor Behavior

These are special values for the destructor that is passed in as the
final argument to routines like sqlite3_result_blob(). R-31518-37056:[If the destructor
argument is SQLITE_STATIC, it means that the content pointer is constant
and will never change.]
It does not need to be destroyed. R-15807-22461:[The
SQLITE_TRANSIENT value means that the content will likely change in
the near future and that SQLite should make its own private copy of
the content before returning.]

The typedef is necessary to work around problems in certain
C++ compilers.